This slide is about Screen Printing Classification and Methods

1. Welcome to our
Presentation

2. BGMEA University of Fashion & Technology
Assignment on: Screen Printing
Presented By:
Md Nazmus Shakib [181-068-101]
Ahnaf Afridi [181-083-101]

3. Introduction to screen printing
INDEX 3
Preparation For Screen Printing
Required Items For Screen
Printing

4. Types of Screen Printing
INDEX 4
Advantages
Disadvantages

5. Screen printing is a printing technique
whereby a mesh is used to transfer ink
onto a substrate, except in areas made
impermeable to the ink by a
blocking stencil. A blade or squeegee is
moved across the screen to fill the open
mesh apertures with ink, and a reverse
stroke then causes the screen to touch
the substrate momentarily along a line
of contact. This causes the ink to wet
the substrate and be pulled out of the
mesh apertures as the screen springs
back after the blade has passed.
One color is printed at a time, so several
screens can be used to produce a
multicolored image or design.
Screen Printing
DEFINITION 5

6. REQUIRED ITEMS FOR SCREEN PRINTING 6
 It refers to the number of the
threads per inch of fabric.
 The usual mesh of screen
employed for cotton and silk
printing is 80 threads per inch.
Screen Screen Frames
 .There are two types of screen
frames(metal & wood)
 Screen frames are usually
26˝×55˝ and 23×55˝ for
printing 45˝ wide cloth.

7. REQUIRED ITEMS FOR SCREEN PRINTING 7
 Silk- Multifilament Weave
 Nylon- Multifilament or
monofilament
 Polyester- Multifilament or
Monofilament
Screen Fabric Types Squeegee
 squeegee is moved
across the screen to
fill the open mesh
apertures with ink

8. PREPARATION OF SCREEN 8
Photochemical method is the most
widely used for preparing the
screen.
This based on the principle
that when a coating of a
solution of ammonium
dichromate-gelatin or
ammonium dichromate-
polyvinyl alcohol is dried
and exposed to light,
insolubilisation takes place.
Other method for screen
preparation is lacquer and laser
screen.

9. TYPES OF SCREEN PRINTING 9
2. Rotary Screen Printing
Upcoming Deposits
1. Flat(bed) screen printing
Fully Automatic Flat Screen
Printing
Semi Automatic Flat Screen
Printing
Hand Screen Printing

10. Hand Screen Printing
Hand Screen Printing is a technique that allows to
print, with greater accuracy, large and bright
images on any type of fabric. It is an ancient
technique, that has envolved over time and is still
one of the most common for textile printing.
Hand Screen printing is made with just a frame,
ink and a stencils. The stencil is the negative of
the image you want to print and is in
waterproofing material.
After mounting the fabric on the frame and
placing the stencil, the ink is spread. The
operation have to be repeated several times if
working with multiple colors. In this case, the
fabric must dry completely between one color
and the next. The technique of Hand Screen
Printing, while being less prone to human error,
requires a high level of competence: the
craftsman who makes the press must be familiar
with the pigments used and the fabric, to be sure
of obtaining a good results.

11. Semi Automatic Flat Screen Printing
The manual process has been semi automated by
mounting the screen in a carriage and driving the
squeegee mechanically across the screen. Long
tables, typically 20-60m long, are used and some
provision is usually made for drying the printed
fabric.
Semi automated flat screen printing is still very
popular where the scale of production is not
large or where capital investment is limited. In
both hand and semi-automatic flat screen
printing the colors are printed one after another
with time for drying, which means that the
situation approaches ‘wet-on-dry’ printing.

12. Rotary Screen Printing
In basic operation, rotary screen and flat screen-
printing machines are very similar. Both use the
same type of in-feed device, glue through,
rotating blanket, dryer and fixation equipment.
The process involves initially feeding fabric onto
the rubber blanket. As the fabric travels under
the rotary screens, the screens turn the white
fabric.
During printing, the paste is pressed through the
surface via openings in order to obtain the
desired design. The cylindrical screens allow
more screens to be arranged per unit length than
is the case with flat screen printing. Speed range
from 30 to 50 m/min. The standard internal
circumference of cylindrical screens is 640 -
640.1 mm. However, other dimensions· are also
possible.

13. Advantages
 The inks used are very durable, the colors are extremely vivid, particularly for outdoor
uses, making this a unique reproduction technique.
 We can print on a very large variety of materials and objects, and that we can choose
from a plethora of special inks.
 This is a very flexible printing technology, with no limitation on the thickness.
13
Advantages of Screen Printing

14. Disadvantages
 The major disadvantage in Screen Printing is the amount of time it takes to set up a job.
 So preparation times are particularly long, particularly in high quality applications.
 This means that, as a method, it is financially impractical for the production of a single
item, particularly for color printing advertising applications.
14
Disadvantages of Screen Printing

15. Any
Questions
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16. THANK
YOU